Overview

Relevant equations documented in ‣. Computations performed using Architect.

Factors

The following factor influence our choice of pointing accuracy:

Ground target error: the limitation of the satellite to point exactly where we want it. Given that there will be a certain uncertainty for the pointing accuracy, this is the maximum distance between where it can point vs where it should point.
Skew angle: the angle at which we point the satellite.

Data

Outcome

Assuming that the orbital altitude is constant at 500 km and our maximum skew angle is 45 degrees, the following table best encapsulates the constraints of pointing accuracy based on ground target error:

Ground Target Error Maximum [m]	Necessary Pointing Accuracy [deg]
50	0.0029
100	0.0057
150	0.0086
200	0.0155
250	0.0144
300	0.0172
350	0.0201
400	0.0229
450	0.0258
500	0.0286

Alternatively, if we again, hold the orbital altitude constant at 500 km, if we set our maximum ground target error to be 100 m, then we can generate the following table.

Skew Angle [deg]	Necessary Pointing Accuracy [deg]
0	0.0115
10	0.0112
20	0.0102
30	0.0086
40	0.0067
45	0.0057
50	0.0047
60	0.0029
70	0.00135

Thus, if we want to limit the ground target error to 100 m, to essentially have no constraints on the skew angle, we would need a pointing accuracy of 0.00135 degrees. Alternatively, if we are constrained by the pointing accuracy to 0.004, then we should not point at a skew angle of much greater than 50 degrees.